Not sure what the limits are but from the reading that I have done, names that come up most are Palms, Orleans, I think Excalibur and either Mirage or Bellagio. Again, I don't know, especially with Mirage and Bellagio, but I think I have heard those as having low limit games. Excalibur and Palms, I think have been mentioned as having classes that will teach you about Casino Hold Em. I have been thinking of stopping in to Palms on my next trip to try a session. Someone mentioned somewhere that Palms even has a special low limit game following the class so that participants can get their feet wet.

That is all from my recallection of recent reading. Hopefully someone will correct me if I am wrong.